Thursday, March 31, 2011

This Could Be a Big Deal: "Scientists use a Harry Potter-like wand to tame fire"

From the Houston Chronicle's SciGuy:

This is so wild I don't even know where to begin. And it's a Sunday, so I'm pretty much going to pass this news release through verbatim:

Scientists today described a discovery that could underpin a new genre of fire-fighting devices, including sprinkler systems that suppress fires not with water, but with zaps of electric current, without soaking and irreparably damaging the contents of a home, business, or other structure.

"Controlling fires is an enormously difficult challenge," said Harvard chemist Ludovico Cademartiri, who reported on the research. "Our research has shown that by applying large electric fields we can suppress flames very rapidly. We're very excited about the results of this relatively unexplored area of research."...

...In the new study, they connected a powerful electrical amplifier to a wand-like probe and used the device to shoot beams of electricity at an open flame more than a foot high. Almost instantly, the flame was snuffed out. Much to their fascination, it worked time and again. ...MORE

That was on the 27th. On Tuesday he followed up with:

Much more on the amazing use of electricity to put out fires

Some readers expressed a burning desire to read more about the seemingly magical fire wand briefly described here on Sunday, so I tracked down one of the scientists who led the work.

Ludovico Cademartiri, a postdoctoral fellow in the research group of George Whitesides, a highly respected chemist at Harvard University, was happy to oblige. As it happens, the potential uses of this technique go far beyond fire control.

Here, then, is my conversation with Cademartiri, who insists I didn't butcher his name.

Tell me exactly what you did in the lab to demonstrate this phenomenon.
The experiments were fairly simple. We generated a methane flame that is tall and thin. Then we generated an electric field in the vicinity of the flame. To do that we used an electrode or metal wire covered with an insulator, which we pointed at the base of the flame. The wire was connected to a high voltage amplifier and the result of this setup is that we exposed the flame to an oscillating field gradient. The response of the flame was that, in certain conditions, especially at very high fields and frequencies, the flame would be literally pushed away from the burner and put out. It was a very strong effect compared to anything that has been shown before in regard to electric fields and flames.

What did you think when the flame went out the first time?
I thought "Well, that's weird." As a scientist you find it fascinating, but you have to control your emotions and ask how nature is trying to deceive you. I was thinking, "What is wrong with this experiment? What did I do wrong?"...MORE